In the present electronic age, display products, such as mobile phone, PMP (Portable Media Player), portable video player, PDA (Personal Digital Assistant), digital camera, pickup camera, display device, portable TV, electronic photo album and the like, have been used widely in our daily life. In general, an electronic apparatus with display screen is provided with a direction key having the functions for selecting the played contents, confirming the playing operation and the like.
In the current electronic apparatuses with display screen, the direction key is generally provided on the front surface where the display screen is positioned, this arranging manner, however, has following drawback: the size of the display screen is relatively small because the direction key occupies a relatively large area of the front surface.
In order to increase the size of the display screen, Japanese patent application publication KOKAI No. 2005-228043A disclosed a display device provided with a rotary direction key which is provided at the upper end of the display device and selects the display contents by rotating in forth-back direction about its rotating axle. In addition, Japanese patent application publication KOKAI No. 2002-157078A also disclosed a display device provided with a rotary direction key which is provided at the left end of the display device and selects the display contents by rotating in forth-back direction about its rotating axle.
However, the display devices disclosed in Japanese patent application publication KOKAI No. 2005-228043A and Japanese patent application publication KOKAI No. 2002-157078A have following drawback: the rotary direction key is not applicable to the display devices having more than three functions because the rotary direction key has the selecting function in two directions only (KOKAI No. 2005-228043A has the selecting function in forth-back direction only and KOKAI No. 2002-157078A has the selecting function in up-down direction only); meanwhile, there is no intuitive relationship of correspondence between the position where the above-mentioned rotary direction key is provided and the display area on the display screen, so that the user can not select the displayed menu items intuitively, simply and conveniently.